A. Field of the Invention
The present invention relates to toilet tank float valves of the type used to control the flow of inlet water to a toilet tank. The invention is especially well suited to be used with toilet tanks in which the cover of the tank defines a sink and a spout dispenses water into the sink.
B. Description of the Art
The need for water conservation has increased in recent years. This has led to many inventions for reducing the amount of water required to flush a toilet. A different approach has been to provide a diverter valve in the toilet tank to direct at least a portion of the inlet water to a lavatory spout on top of the tank during the flush cycle. After using the toilet, the user can wash his or her hands under the spout, and then that water drains back into the tank for use in cleaning the toilet bowl during the next flushing cycle.
In one prior art device of this kind there is a diverter valve in the tank with a single inlet and three outlets. One of the outlets feeds water to the spout, a second feeds water to an overflow outlet tube, and a third feeds water directly into the toilet tank. A lever linkage is provided to transmit energy from a float (which follows the water level) to a piston valve which shuts off the water flow to the three outlets when the water has refilled the tank.
Because such valves can be installed in many different size toilets, it is desirable to provide a means for adjusting the float position (and thus the level of water) in the tank which will cause the inlet valve to shut off the water supply to the toilet tank. These adjustments have in the past been made through complex linkages positioned directly under the piston valve. Not only was this adjustment mechanism difficult to reach, it suffered from the use of multiple parts (some of which were expensive to machine), and further did not provide a complete range of adjustment.
In another prior art valve the float rod arm was made so that it could be bent. While this bending adjusted the closing position, it also caused a shortening of the effective lever distance of the rod, thus changing the closing force on the piston valve. In order to achieve an adjustment one would have to change (and in some cases adversely affect) closing pressure.
In another valve, a slot was provided in the rod such that a connecting link could be adjustably positioned along the rod at several positions in the slot. This required several extra components, and required a plumber or other person desiring to make the adjustment to make both a rotational change and a sliding change at a position largely hidden from view by the valve.
It can therefore be seen that a need has existed for an improved means of providing adjustment of the fill level in a toilet tank.